A gas occupies a volume of 140 mL at 35 degrees celsius and 97 kPa. What is the volume of the gas at STP?

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(P1V1)/T1 = (P2V2)/T2

To find the volume of the gas at STP (Standard Temperature and Pressure), we need to use the ideal gas law. The ideal gas law equation is:

PV = nRT

Where:
P = pressure
V = volume
n = number of moles
R = ideal gas constant (0.0821 L·atm/(mol·K))
T = temperature in Kelvin

First, we need to convert the temperature from Celsius to Kelvin. The conversion is:

T(K) = T(°C) + 273.15

So, the temperature in Kelvin is:

T(K) = 35 + 273.15 = 308.15 K

Now we have all the necessary values except the number of moles (n). To find the number of moles, we can use the ideal gas equation again:

n = PV / RT

Let's calculate the number of moles first:

n = (97 kPa) * (140 mL) / (0.0821 L·atm/(mol·K) * 308.15 K)

Note: We need to convert mL to L, so dividing by 1000:

n = (97 kPa) * (0.14 L) / (0.0821 L·atm/(mol·K) * 308.15 K)

n = 0.0011269 mol

Now we have all the values to find the volume at STP. At STP, the pressure is 1 atm, and the temperature is 273.15 K. So, we can use the ideal gas equation again to find the volume:

V(STP) = nRT / P(STP)

V(STP) = (0.0011269 mol) * (0.0821 L·atm/(mol·K)) * (273.15 K) / (1 atm)

V(STP) = 0.0246 L

Therefore, the volume of the gas at STP is approximately 0.0246 L.

To find the volume of the gas at STP (Standard Temperature and Pressure), we need to use the ideal gas law equation: PV = nRT, where P is the pressure, V is the volume, n is the number of moles of gas, R is the ideal gas constant, and T is the temperature.

STP is defined as a temperature of 0 degrees Celsius or 273.15 Kelvin and a pressure of 1 atmosphere or 101.3 kilopascals (kPa).

Given:
Initial volume (V1) = 140 mL
Initial temperature (T1) = 35 degrees Celsius
Initial pressure (P1) = 97 kPa

First, we need to convert the given values to appropriate SI units:
Volume: 140 mL = 140/1000 L = 0.14 L
Temperature: 35 degrees Celsius = 35 + 273.15 Kelvin = 308.15 K
Pressure: 97 kPa

We can rearrange the ideal gas law equation to solve for the final volume (V2) at STP:
V2 = (nR * T2) / P2

Since we are comparing the initial and final states of the same gas, the number of moles (n) and the gas constant (R) will remain constant.

Now, substitute the given values and the STP values into the equation:
P2 = 101.3 kPa (STP pressure)
T2 = 273.15 K (STP temperature)

V2 = (0.14 L * 308.15 K) / (97 kPa)

Calculate the final volume:
V2 = (0.14 L * 308.15 K) / (97 kPa) = 0.444 L

Therefore, the volume of the gas at STP is 0.444 L.